JPH0621194B2 - Adhesive composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a liquid curable pressure-sensitive adhesive composition having extremely good adhesive properties (tack, adhesive strength, holding power).

[Problems to be Solved by Conventional Techniques and Inventions] Pressure-sensitive adhesives are also called pressure-sensitive adhesives and have the property of easily adhering to the surface of an object with a small pressure that is pressed by a fingertip.

Examples of applications of the adhesive include cellophane tape, vinyl tape for electrical insulation, masking tape, adhesive sheet, adhesive label and the like.

The polymers most often used as adhesives are diene or polyacrylic polymers. Usually, these polymers are solids or liquids of high viscosity, and as such, it is difficult to add a compound such as a tackifying resin or apply it to a substrate such as a tape, a sheet or a label. Therefore, as a method for producing a product using an adhesive (hereinafter referred to as an adhesive product), there is a method using a solvent-type adhesive, a method using an emulsion-type adhesive, a method using a hot-melt adhesive, or the like. .

The most common method is to use a solvent-based adhesive,
Although a polymer with good workability is used by dissolving it in a solvent or polymerizing a monomer in the solvent, a process for removing a large amount of organic solvent is essential, so a facility for recovering the solvent is required. . Further, there is a problem that heat energy for evaporating the solvent is required, which is costly, and there are also problems in working environment, disaster prevention and pollution.

In order to solve these problems of the solvent type, acrylic emulsion type adhesives and rubber type hot mel type adhesives have been introduced as solventless adhesives. The former is one in which the acrylic monomer is emulsion polymerized in water using an emulsifier to improve workability as an aqueous emulsion.
It has the drawbacks of insufficient water resistance and an acrylic odor. The latter is a polymer that can be used without solvent by using a rubber-type polymer that has become a low-viscosity liquid at high temperature, but it is problematic in terms of heat resistance and tack, which is an important property of adhesives. However, there is not enough satisfaction.

In order to overcome the above-mentioned drawbacks of the solvent type, emulsion type and hot melt type pressure-sensitive adhesives, liquid curable pressure-sensitive adhesives have been proposed.

The liquid curable pressure-sensitive adhesive has a small molecular weight before curing and therefore has a low viscosity even at room temperature, so workability such as application to a substrate is good without using a solvent, and it can be used as a pressure-sensitive adhesive after curing. It is an adhesive that increases the molecular weight to some extent. Various liquid-curable pressure-sensitive adhesives have been proposed, and as one of them, a pressure-sensitive adhesive composition composed of a rubber-based organic polymer having at least one reactive functional group has been proposed (Japanese Patent Laid-Open Publication No. Sho. 59-71377 public information). The reactive silicon functional group in the rubber-based organic polymer forms a siloxane bond due to moisture at the time of curing, crosslinks into a high molecular weight, and at this time, a tackifying resin is blended to develop tackiness. Although the pressure-sensitive adhesive composition has excellent advantages such as heat resistance and low-temperature characteristics, it does not necessarily have sufficient characteristics, and further improvement in characteristics is desired.

More specifically, the following three characteristics are required as the three basic characteristics of the adhesive.

Adhesiveness (Adhesive products such as tapes are attached to the adhesive surface,
The force required to peel off the adhesive surface after applying sufficient pressure and time. Larger size is usually better, depending on the application. ) Tack (the degree of stickiness on the surface of the adhesive. It is a measure of how easily it sticks to the adherend. Generally, it should be large.) Holding power (creep resistance. When a force parallel to the adhesive surface is applied to the base material) The length of displacement of the relative position between the base material and the object to be bonded. The shorter the deviation, the better.) In the case of the pressure-sensitive adhesive composition comprising the rubber-based organic polymer having the reactive silicon functional group, In order to have sufficient holding power, it is necessary to increase the content of reactive silicon functional groups in the rubber-based organic polymer so as to increase the number of cross-linking points during curing, and to achieve a sufficient high molecular weight. Is. However, when the content of the reactive silicon functional group is increased, the adhesive strength / tack becomes low level.

A tackifying resin is blended in order to improve this low level of tack and tack. The tackiness is improved in proportion to the amount of tackifying resin, and standard tackiness can be obtained by adding a large amount of tackifying resin. The tack is maximized when the tackiness is relatively low, that is, when the tackifying resin amount is low, and then rapidly decreases with the tackifying resin amount. Moreover, the maximum value is not enough. Therefore, when the above-mentioned composition is used, there is a limit in obtaining a composition having good adhesion and tack at the same time.

The tackifier resin usually has a low molecular weight, has an unsaturated group and other functional groups, and its physical properties are highly temperature-dependent, so add a large amount of tackifier resin to obtain standard tackiness. Then, another problem such as deterioration of weather resistance and deterioration of high temperature characteristics occurs.

From the above, it is considered that if a pressure-sensitive adhesive having a good tack and tack can be obtained by adding a relatively small amount of tackifying resin, it will be an extremely useful pressure-sensitive adhesive.

The present invention is to solve the problem that a pressure-sensitive adhesive composition having sufficient pressure-sensitive adhesive properties cannot be obtained even if a large amount of a tackifying resin is added to a rubber-based organic polymer having a reactive silicon functional group. It was made.

[Means for Solving Problems] The present invention provides (a) 100 parts by weight of a moisture-curable rubber-based organic polymer having at least one reactive silicon functional group in a molecule (parts by weight, hereinafter the same). , (B) Two hydroxyl or hydrolyzable groups on the silicon atom
A silicon compound having one silicon atom and / or at least one hydroxyl group or hydrolyzable group on one silicon atom, and the total number of hydroxyl groups or hydrolyzable groups is 2 to 5 The present invention relates to an adhesive composition containing 0.1 to 50 parts of a silicon compound having 2 to 20 silicon atoms and (c) 5 to 120 parts of a tackifying resin.

By using the composition, even if the amount of the tackifying resin is reduced as compared with the composition containing no component (b), it is possible to obtain an adhesive composition having excellent adhesive strength and tack.

[Examples] As the polymer forming the skeleton of the moisture-curable rubber-based organic polymer having at least one reactive silicon functional group in the molecule which is the component (a) used in the present invention, for example, propylene can be used. Alkylene oxide polymer system (polyether system) obtained by polymerization of cyclic ether such as oxide, ethylene oxide and tetrahydrofuran; 2 such as adipic acid
Polyester system obtained by condensation of basic acid and glycol or ring-opening polymerization of lactones; ethylene-propylene copolymer system; polyisobutylene or copolymer system of isobutylene and isoprene; polychloroprene; polyisoprene or isoprene and butadiene, Copolymer system with styrene, acrylonitrile, etc .; Copolymer system with polybutadiene or butadiene and styrene, acrylonitrile, etc .; Polyolefin system obtained by hydrogenating polyisoprene, polybutadiene or a copolymer of isoprene and butadiene; Ethyl acrylate, Polyacrylic acid ester obtained by radical polymerization of vinyl monomer such as butyl acrylate, or copolymer of acrylic acid ester with vinyl acetate, acrylonitrile, styrene, ethylene, etc. A polymer system obtained by polymerizing one or more vinyl monomers such as a coalesced polymer; a graft polymerization system obtained by polymerizing vinyl monomers in the rubber-based organic polymer used in the present invention; a polysulfide system, etc. Examples include polymers. Among these, polyalkylene oxide polymers having a repeating unit represented by the general formula such as polypropylene oxide: —R ² —O— (in the formula, R ² represents a divalent alkylene group having 2 to 4 carbon atoms). Acrylic acid ester in the presence of polyalkylene oxide polymer such as polypropylene oxide,
Polymers or copolymers such as graft polymers obtained by polymerizing one or more vinyl monomers such as styrene, acrylonitrile and vinyl acetate, polyacrylic acid esters or acrylic acid esters and vinyl acetate, acrylonitrile, styrene, A copolymer with ethynylene or the like is preferable in that a reactive silicon functional group can be easily introduced at the molecular end, a liquid polymer can be easily produced without a solvent, and a well-balanced adhesive property can be easily obtained. Further, from the viewpoints of good water resistance, low cost, and easy handling as a liquid, a polymer mainly containing propylene oxide and / or alkyl acrylate, that is, propylene oxide and / or alkyl acrylate A polymer containing 50% (wt%, the same applies hereinafter) or more is preferable.

Examples of the reactive silicon functional group contained in the rubber organic polymer include a hydrolyzable silicon group or a silanol group.

The reactive silicon functional group referred to in the present specification, in the presence or absence of a silanol condensation catalyst, a silanol condensation-reactive hydroxyl group or a hydrolyzable group capable of being hydrolyzed by moisture is condensed to a silicon atom. Means a group
Typically, the general formula (1): (In the formula, R ¹ is a monovalent hydrocarbon group having 1 to 12 carbon atoms selected from an alkyl group and an aryl group, x is a hydroxyl group or a hydrolyzable group, a is 0, 1, 2 or 3, and b is 0, 1 or 2, where 1 ≦ a + b ≦ 4 and n represents an integer of 0 to 19) can be exemplified.

Specific examples of the hydrolyzable group include hydrogen atom, halogen atom, alkoxy group, acyloxy group, ketoximate group, amino group, amido group, aminooxy group, mercapto group, alkenyloxy group and other commonly used groups. can give. Of these, alkoxy groups are particularly preferable because they have mild hydrolyzability and are easy to handle. The hydrolyzable group has 1 to 1 silicon atom.
Can be combined in the range of ~ 3. Among the reactive silicon functional groups represented by the formula (1), a reactive silicon functional group in which b = 2 and a = 0 or 1 is preferable.

The number of silicon atoms forming the reactive silicon functional group may be one or two or more, but in the case of silicon atoms connected by a siloxane bond or the like, up to 20 silicon atoms can be used. You can use it freely.

Examples of the method for introducing the reactive silicon functional group into the rubber-based organic polymer include the following methods.

(1) Ethylene and propylene are monomers having a copolymerizable unsaturated group and a reactive silicon functional group in the molecule, such as vinyltrialkoxysilane, methacryloyloxypropylmethyldialkoxysilane, and methacryloyloxypropyltrialkoxysilane. , Isobutylene, chloroprene, isoprene, butadiene, acrylic acid ester, etc.
-Copolymerizing a monomer having a copolymerizable epoxy group such as glycidoxypropyltrimethoxysilane and γ-glycidoxypropylmethyldimethoxysilane in the molecule and a reactive silicon functional group with propylene oxide or ethylene oxide Method.

By these methods, a reactive silicon functional group can be introduced into the molecular side chain.

(2) Silicon having a reactive silicon functional group and a mercapto group such as mercaptopropyltrialkoxysilane and mercaptopropylmethyldialkoxysilane capable of causing a chain transfer reaction in a reactive silicon functional group, and a reactive silicon functional group in the molecule. A method of polymerizing a radically polymerizable monomer using a compound as a chain transfer agent.

(3) Radical-polymerizable monomer using an azo-based or peroxide-based polymerization initiator containing a reactive silicon functional group such as azobis-2- (6-methyldiethoxysilyl-2-cyanohexane) A method of polymerizing.

In the methods (2) and (3), a reactive silicon functional group is introduced at the polymer molecule terminal.

(4) A polymer having a functional group such as a hydroxyl group, a carboxyl group, a mercapto group, an epoxy group and an isocyanate group (hereinafter referred to as a Y functional group) at a side chain and / or a terminal of the polymer is used, and the Y functional group is used. A method of reacting a silicon compound containing a Y'functional group capable of reacting with a group in a molecule and having a reactive silicon functional group with the Y functional group. Specific reaction examples are shown in the following table, but not limited thereto.

In particular, as the polymer having a Y functional group used as the starting material and intermediate material in the table, polyoxypropylene polyol, polyoxyethylene polyol,
Main chain in essentially ^-R 2 -O- (wherein like polyoxytetramethylene diol, ^{R 2} is C2-4 2
Represents a divalent alkylene group), a polyether polyol having a repeating unit represented by the formula; a polyester polyol obtained by condensation of a dibasic acid such as adipic acid and glycol or ring-opening polymerization of a lactone; a polyisobutylene polyol or Polycarboxylic acids; Polybutadiene or copolymers of butadiene and styrene, acrylonitrile or the like; or polycarboxylic acids; polyolefins obtained by hydrogenating polyisoprene or polybutadiene; polyols or polycarboxylic acids and polyisocyanates; Isocyanate functional group-containing polymers obtained by reacting with; a vinyl-type unsaturated group-containing polymer obtained by reacting the polyols with a polyvalent halogen compound and a vinyl-type unsaturated group-containing halogen compound, etc. It is particularly preferable, wherein the polymer compound further Y functional group is more preferable in the polymer molecular terminal.

Examples of the silicon compound having the Y ′ functional group include γ- (2-
Aminoethyl) aminopyropyrtrimethoxysilane, γ-
Amino group-containing silanes such as (2-aminoethyl) aminopropylmethyldimethoxysilane and γ-aminopropyltrimethoxysilane; mercapto groups such as γ-mercaptopropyltrimethoxysilane and γ-mercaptopropylmethyldimethoxysilane Contained silanes; γ
-Glycidoxypropyltrimethoxysilane, β- (3,4-
Epoxycyclohexyl) Epoxysilanes such as ethyltrimethoxysilane; Vinyl type unsaturated group-containing silanes such as vinyltriethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-acryloyloxypropylmethyldimethoxysilane;
Base atom-containing silanes such as γ-chloropropyltrimethoxysilane; isocyanate-containing silanes such as γ-isocyanatopropyltriethoxysilane and γ-isocyanatopropylmethyldimethoxysilane; methyldimethoxysilane, trimethoxysilane, methyl Specific examples thereof include hydrosilanes such as diethoxysilane, but are not limited thereto.

In the combination of a polymer having a Y functional group and a silicon compound having a Y ′ functional group, particularly, (i) a polymer having an isocyanate group and an amino group-containing silane or a mercapto group-containing silane are combined. , (Ii) A combination of a vinyl type unsaturated group-containing polymer and a hydrosilane is preferable. Further, in (ii), a combination of polypropylene oxide having an allyl ether group at the molecular end and hydrosilanes is particularly preferable. In (ii), a silyl group may be introduced into the polymer by reacting a vinyl group and a hydrosilyl group by using a hydrosilylation reaction using a platinum compound as a catalyst.

At least 1 in the molecule of component (a) used in the present invention
As the molecular weight of the moisture-curable rubber-based organic polymer having one, preferably 1.4 to 6 reactive silicon functional groups,
A liquid material of about 500 to 50,000, especially about 3,000 to 20,000 is particularly preferable from the viewpoint of easy handling. If the number of reactive silicon functional groups contained in the molecule is less than 1, the curing may be insufficient and the creep resistance may be deteriorated.

In the rubber-based organic polymer having at least one reactive silicon functional group in the molecule used in the present invention, the reactive silicon functional group is preferably present at the molecular end.

Specific examples of the component (a) as described above include, for example, JP-B-45-36319, JP-B-46-12154, JP-B-49-32673, and JP-A-
50-156599, 51-73561, 54-6096, 55-13767
No. 54, No. 54-13768, No. 55-82123, No. 55-123620, No.
55-125121, 55-131021, 55-131022, 5
5-135135, 55-137129, 57-179210, 58-
191703, 59-78220, 59-78221, 59-78222
No. 59-78223, No. 59-168014, and the like are disclosed, and these are effectively used, but not limited thereto.

The component (b) used in the present invention is a silicon compound having two hydroxyl groups or hydrolyzable groups on a silicon atom and having one silicon atom, and / or a hydroxyl group or hydrolyzable group on one silicon atom. It is a silicon compound having 2 to 20 silicon atoms and having 2 to 5 hydroxyl groups or hydrolyzable groups in total.

It is considered that the silicone compound functions to adjust the amount and reactivity of the reactive silicone functional group of the rubber-based organic polymer as the component (a), and convert the rubber-based organic polymer into a structure suitable as an adhesive. To be

The silicon compound having one silicon atom is typically represented by the general formula (2): Can be expressed as R ³ and R ⁴ in the formula are monovalent organic groups, and in the organic groups, a halogen atom, a hydroxyl group, an alkoxy group, a nitrile group, an amino group, a mercapto group, an acid amide group, a carboxylic acid group, and epoxy are included. A functional group such as a group or an acryloyl group may be included. M, N
Is a functional group capable of reacting with the reactive silicon functional group in the rubber organic polymer as the component (a), a halogen atom, a hydrogen atom, a hydroxyl group, an alkoxy group, an acyloxy group, a ketoximate group, an amide group, an acid amide group, It is an aminooxy group, an alkenyloxy group or a mercapto group, but a hydroxyl group or an alkoxy group is particularly preferable.

Specific examples of the silicon compound represented by the general formula (2) include (CH ₃ ) ₂ Si (OCH ₃ ) ₂ and (CH ₃ CH ₂ ) ₂ Si (OC
_{H 3) 2, (CH 3} ) 2 Si (OCH 2 CH 3) 2, (CH 3 CH 2) 2 Si (OCH 2 CH 3)
₂ , _{(CH 3) 2 Si (OCH} 2 CH 2 OCH 3) 2, (CH 3 CH 2) 2 Si (OCH 2 CH 2 OCH 3) 2, (CH 3) (CH 3 CH 2) Si (OCH 3) 2 , However, the present invention is not limited to these.

In the present invention, the specific silicon compound having 2 to 20 silicon atoms described above is used as the component (b) instead of or in addition to the compound having 1 silicon atom represented by the general formula (2). Good.

Specific examples of the specific silicon compound include: (X + y = 0 to 18), (X + y = 0 to 18), (1 ≦ x + y + z ≦ 19), (1 ≦ x + y + z ≦ 19), (1 ≦ x + y + z ≦ 19), (1 ≦ x + y + z ≦ 19), However, the present invention is not limited to these.

Among these compounds used as the component (b), compounds having an aryl group such as a phenyl group, a naphthyl group, or a substituted phenyl group, particularly a phenyl group or a tolyl group on a silicon atom to which a hydroxyl group or a hydrolyzable group is bonded are Silanol condensation reaction itself, which can be selectively reacted with the reactive silicon functional group in the rubber-based organic polymer of the component (a), has good stability in air, is easy to handle, and is particularly preferable. .

Further, these compounds are more effective at the same addition amount as the number of functional groups per the same molecular weight is larger, and those having 5 or less silicon atoms are preferable. As a particularly preferable silicon compound, (Wherein x represents a hydroxyl group or a hydrolyzable group, R ⁵ represents a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms), and specific examples thereof include: Be done.

The mechanism of the improving effect of these silicon compounds as the component (b) has not been sufficiently clarified, but it is estimated from the actual effect as follows.

First, by reacting a silicon atom of these silicon compounds with a hydroxyl group or a hydrolyzable group and a reactive silicon functional group of the rubber-based organic polymer of the component (a), in the rubber-based organic polymer ( (B) The silicon compound of the component is introduced, and the silanol group or the hydrolyzable group existing after the reaction on the silicon atom of the silicon compound and the reactive silicon functional group remaining in the rubber-based organic polymer are effective. It is considered that a cured product having a molecular weight between cross-linking points and a cross-linking density suitable for a pressure-sensitive adhesive is obtained by carrying out chain extension, cross-linking, ring forming reaction and the like.

Regarding the number of hydroxyl groups or hydrolyzable groups on the silicon atom of the silicon compound of the component (b) used in the present invention, in the case of the compound having one silicon atom, the number is 2, and the number of the silicon atom is 2 to 20. In the case of compounds, it is preferable that the number is at most one on one silicon atom and the total is 2 to 5.
If the number of hydroxyl groups or hydrolyzable groups on the silicon atom is larger than this, the crosslink density of the cured product becomes too high and it becomes difficult to develop sufficient tackiness. If so, the crosslink density becomes too low, and the holding power and curability of the cured product decrease.

Regarding the amount of the silicon compound of the component (b) used in the present invention, it depends on the expected physical properties of the cured product, the content of the silanol group or the hydrolyzable group on the silicon atom of the silicon compound used, etc. It is preferable that the silanol group or the hydrolyzable group in the silicon compound as the component (b) is 0.12 equivalent to the reactive silicon functional group of the rubber-based organic polymer, and it is 0.3 to 1 equivalent. This range is more preferable. The actual amount of use is 0.1 to 50 parts, preferably 0.3 to 20 parts, based on 100 parts of the rubber organic polymer as the component (a). Further, depending on the expected physical properties, these silicon compounds as the component (b) may be used alone or in combination of two or more kinds.

Although a tackifying resin is used as the component (C) in the present invention, the tackifying resin is not particularly limited, and has a polar group such as rosin ester resin, phenol resin, xylene resin, xylene phenol resin, and terpene phenol resin. Resin, aromatic system with relatively small polarity,
Various petroleum resins such as an aliphatic-aromatic copolymer system or an alicyclic system, or usual tackifying resins such as coumarone resin, low molecular weight polystyrene resin, and terpene resin can be used.

These resins and specific examples include Petrozine 80 (manufactured by Mitsui Petrochemical Co., Ltd.), Neopolymer S (manufactured by Nippon Petrochemical Co., Ltd.), Tack Ace A100 (Mitsui Petrochemical Co., Ltd.).
), Quinton 1500 (manufactured by Nippon Zeon Co., Ltd.), FTR610
0 (manufactured by Mitsui Petrochemical Co., Ltd.), Picolastec A75 (manufactured by Hercules Co., Ltd.), Kumaron G-90 (Nittetsu Chemical Co., Ltd.)
Resin) and YS Polystar T-11
5, YS Polystar S-145 (all manufactured by Yasuhara Yushi Co., Ltd.),
Examples thereof include resins having polar groups such as steberite ester 7 (manufactured by Hercules Co., Ltd.) and neopolymer E-100 (manufactured by Nippon Petrochemical Co., Ltd.), but are not limited thereto.

The number of parts of the tackifying resin used as the component (c) depends on its type and amount, but is in the range of 5 to 120 parts, preferably 20 to 100 parts, relative to 100 parts of the rubber organic polymer of the component (b). Used in. If the amount is less than 5 parts, the adhesive strength and tack are insufficient, and if it is more than 120 parts, good tack properties cannot be obtained. Especially, it is recommended to use less than 100 parts.

In the present invention, a catalyst may be used to accelerate the curing reaction by silanol condensation. As the curing catalyst, for example, dibutyltin dilaurate, tin dioctylate, dioctyltin maleate, a reaction product of dibutyltin oxide and a phthalic acid ester, an organic tin compound such as dibutyltin diacetylacetate, Japanese Patent Application No. 59-
Di-n-butoxyzirconium diacetylacetonate, n-butoxyzirconium triacetylacetonate, diisopropoxyaluminum acetylacetate, aluminum triacetal acetate, diisopropoxyaluminum ethylacetoacetate, aluminum disclosed in 183097. Zirconium or aluminum compounds such as triethylacetoacetate, carboxylic acid metal salts such as alkyl titanate, amines such as dibutylamine-2-ethylhexoate, acidic catalysts and bases used as ordinary silanol condensation catalysts. Examples include a sex catalyst. The amount of these catalysts used is 0.1 to 20 parts with respect to 100 parts of the rubber-based organic polymer as the component (a). When the amount is less than 0.1 part, the catalytic effect is small, and when it exceeds 20 parts, the curing is too fast and the work of applying to the support becomes difficult.

In the present invention, if necessary, a plasticizer or a softening agent such as dioctyl phthalate, butylbenzyl phthalate, polypropylene glycol, chlorinated paraffin, liquid polybutadiene; calcium carbonate, clay, talc, titanium oxide, zinc white, silica, diatomaceous Fillers such as soil and barium sulfate; antioxidants, ultraviolet absorbers, pigments, surfactants and the like may be added as appropriate.

Further, a solvent may be added for the purpose of improving workability and lowering the viscosity. For example, an aromatic hydrocarbon solvent such as toluene and xylene, an ester solvent such as ethyl acetate, butyl acetate, amyl acetate and cellosolve acetate. Examples thereof include ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, and diisobutyl ketone.

Next, a method for producing the composition of the present invention will be described.

There are two general methods for producing the composition of the present invention.

The first method is a method in which the silicon compound as the component (b) is simply added to the mixture containing the rubber-based organic polymer as the component (a).

The heating and stirring conditions may be adjusted according to the properties of the silicon compound and the like to uniformly disperse and dissolve. In this case, it is not necessary to have a completely uniform and transparent state, and even if it is in an opaque state, the object can be sufficiently achieved if it is dispersed. If necessary, a dispersibility improving agent such as a surfactant may be used in combination.

The second method is to react the silicon compound of component (b) with the rubber-based organic polymer of component (a) in advance. If necessary, tin catalyst, titanate ester catalyst, acid or basic In the case of using a compound such as a catalyst together with a compound having a hydrolyzable group on the silicon atom of the silicon compound, the addition amount of water is also added, and the product is heated under a reduced pressure to be devolatilized. Is achieved.

Examples of the catalyst that can be used at this time include titanic acid esters such as tetrabutyl titanate and tetrapropyl titanate; organic tin compounds such as dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, tin octylate, tin naphthenate; octylic acid. Lead: butylamine, octylamine, dibutylamine, monoethanolamine, diethanolamine, triethanolamine, diethylenetriamine, triethylenetetramine, oleylamine, octylamine, cyclohexylamine, benzylamine, diethylaminopropylamine, xylylenediamine, triethylenediamine, granidine, Diphenylguanidine, 2,4,6-tris (dimethylaminomethyl) phenol, morpholine, N-methylmorpholine, 1,3-diaza Cyclo (5,4,6) undecene -7 (D
BU) and other amine compounds or their carboxylic acid salts; low molecular weight polyamide resins obtained from excess polyamine polybasic acid; reaction product of excess polyamine and epoxy compound; silane coupling agent having amino groups , For example γ-aminopropyltrimethoxylane,
A specific example is a silanol condensation catalyst such as N- (β-aminoethyl) aminopropylmethyldimethoxysilane. These may be used alone or in combination of two or more.

Since the pressure-sensitive adhesive composition of the present invention has excellent adhesive strength and tack, it can be widely used for tapes, sheets, labels, foils and the like. That is, for example, synthetic resin or modified natural film, paper, various kinds of cloth, metal foil, metallized plastic foil, asbestos or glass fiber cloth, etc. Alternatively, the pressure-sensitive adhesive composition may be applied in the form of a hot melt type, exposed to moisture or water, and cured at room temperature or heat.

Hereinafter, the pressure-sensitive adhesive composition of the present invention will be described in more detail with reference to examples.

Synthetic Example 1 800 g of polypropylene oxide having an average molecular weight of 8000 and containing allyl ether groups at 90% of all terminals.
In a pressure resistant reactor equipped with a stirrer, 20 g of methyldimethoxysilane was added, followed by a catalyst solution of chloroplatinic acid (H ₂ PtCl ₂
0.34 ml of a solution prepared by dissolving 8.9 g of ₆ · 6H ₂ O in 18 ml of isopropyl alcohol and 160 ml of tetrahydrofuran was added, and the mixture was reacted at 80 ° C. for 6 hours. As a result of quantifying the reaction rate from the gas chromatogram and IR spectrum, 88% of the end
Know that they are reacting, A polypropylene oxide having 81% of all terminals was obtained.

Synthesis Example 2 81% of all the ends synthesized in Synthesis Example 1 90 g of a reactive silicon functional machine-terminated propylene oxide polymer having an average molecular weight of 8000 is placed in a reaction vessel, delumined under reduced pressure, and nitrogen replacement is performed, followed by heating to 110 ° C.,
It was stirred. Separately prepared n-butyl acrylate 3
A mixture of 0.9 g, 0.3 g of γ-methacryloxypropyldimethoxymethylsilane and 0.3 g of AIBN was added dropwise over 1 hour under a nitrogen atmosphere. 15 minutes and 30 minutes after dropping
After minutes, 0.0015 g of each AIBN was dissolved in 4 times by weight acetone and added. After the addition was completed, stirring was continued for 30 minutes to terminate the polymerization reaction.

The obtained polymer was a slightly yellow transparent and viscous liquid, and the amount of residual monomer by GC analysis was 1% and the viscosity was 540P (23 ° C, measured by B-type viscometer).

Synthesis Example 3 100 g of n-butyl acrylate, 1.64 g of γ-methacryloxypropylmethyldimethoxysilane, 2.11 of γ-mercaptopropylmethyldimethoxysilane and 0.33 g of neopentyl glycol diacrylate were mixed, and AIBN of 0.26 g was mixed.
Was added and dissolved by stirring. 300 ml 4 equipped with a cooling tube, a dropping funnel and a stirrer, in which 30 g of the mixture was replaced with dry nitrogen gas
The flask was placed in a two-necked flask and heated in an oil bath (80 ° C.) under a nitrogen atmosphere. Polymerization started after a few minutes and an exotherm was observed, and the contents thickened. After the exotherm was moderated, the remaining mixed solution was gradually disintegrated from the dropping funnel. The total amount was dropped in about 3 hours. 20% of AIBN 15 minutes and 30 minutes after the end of dropping
Acetone solution was added in 60 μm increments, and heating and stirring were continued for another 30 minutes to complete the polymerization reaction.

The obtained polymer was a colorless and transparent viscous liquid, and the residual monomer amount by GC analysis was 1.5% and the viscosity was 300 P (23 ° C., measured by B-type viscometer).

Examples 1 to 12 and Comparative Examples 1 to 9 100 parts of polypropylene oxide having the reactive silicon functional group obtained in Synthesis Example 1, 100 parts of the silicon compound shown in Table 1, and Nocrac as an antioxidant NS-6
1 part (manufactured by Ouchi Shinko Chemical Industry Co., Ltd.), a tackifying resin (manufactured by Yasuhara Yushi Co., Ltd. with a softening point of 115 ° C. is YS Polystar)
The T-115 resin was dissolved in toluene beforehand to make a 60% solution, and the amount (solid content conversion) and an appropriate amount of toluene shown in Table 1 were added, and the mixture was thoroughly stirred and uniformly dissolved to obtain a solid content concentration of 60. % Solution was obtained. To this, 3 parts of dibutyltin diacetonate as a curing catalyst was added to the polypropylene oxide, and the mixture was well stirred with a spatula.

The composition obtained was applied onto a 25 μm polyester substrate (Lumirror film manufactured by Toray Industries, Inc.) and the paste thickness after drying was 25.
It was coated with a coater so as to have a thickness of μm, and heat-treated at 120 ° C. for 3 to 5 minutes using a hot air dryer.

The obtained adhesive property test was performed by the following method.

(Tack) Measured using the J.Dow rolling ball tack method. The maximum diameter (x 1/32 inch) of a ball that is stationary at an approach distance of 10 cm, a tilt angle of 30 ° and a temperature of 23 ° C is displayed.

(Holding power) Attached to a stainless steel plate adherend with an area of 25 mm × 25 mm, 1
Suspend a 1kg weight at 00 ℃ to make it a static load, and measure the distance after 60 minutes.

(Adhesive strength) Attached to a stainless steel plate adherend and left at 23 ° C for 24 hours.
Measure 180 ° peel strength at ℃ and tensile speed of 300 mm / min.

As is clear from the results shown in Table 1, when the silicon compound as the component (b) is not used, the tack and the adhesive strength are low as seen in Comparative Examples 1 to 3. Further, it can be seen that the effect of the silicon compound in which a phenyl group is bonded to a silicon atom having a hydroxyl group or a methoxy group is particularly remarkable. Further, the number of hydroxyl groups or methoxy groups is from Comparative Example 4 to
As can be seen from 9, neither too much nor too little is not good.

Examples 13 to 22 and Comparative Examples 10 to 14 Compositions were prepared and evaluated in the same manner as in Examples 1 to 12 except that the types and amounts of silicon compound and tackifying resin were changed as shown in Table 2. . The results are shown in Table 2.

YS Polystar S-145 in Table 2 is Yasuhara Yushi Co., Ltd.
Made, Erpen phenol resin with softening point 145 ℃, FRT6100
Is Mitsui Petrochemical Co., Ltd., petroleum resin with a softening point of 97 ° C, Picolastic A-75 Hercules Co., styrene resin with a softening point of 75 ° C, Quinton 1500 is Nippon Zeon Co., Ltd.
Neopolymer E-100, an ester-modified alicyclic resin with a softening point of 100 ° C, is a petroleum-based resin with a softening point of 90 ° C manufactured by Nippon Petrochemical Co., Ltd.

As is clear from Table 2, it can be seen that the adhesive property is also improved by using the silicon compound (b),
It can be seen that the present invention is a technique that can be applied to a wide range of adhesives.

Examples 23 to 40 and Comparative Examples 15 to 32 Using the rubber-based organic polymers obtained in Synthesis Examples 2 and 3, adhesive tapes were produced in the same manner as shown in Examples 1 to 12, and the adhesive properties ( Tack, holding power, adhesive strength) were measured.
The results using the polymer of Synthesis Example 2 are shown in Table 3, and the results using the polymer of Synthesis Example 3 are shown in Table 4.

For comparison, Table 3 and Table 4 show the results when the silicon compound was not added and the results when the silicon compound other than the silicon compound used in the present invention was added. Table 5 shows the results of evaluation of the performances of the commercially available adhesive products in order to see their levels.

[Effects of the Invention] When the composition of the present invention is used as a pressure-sensitive adhesive, the composition has good adhesive strength and tack at the same time, and the composition of the tackifying resin has at least sufficient adhesive properties. Become.

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Claims (10)

[Claims] 1. (a) 100 parts by weight of a moisture-curable rubber organic polymer having at least one reactive silicon functional group in a molecule, (b) a hydroxyl group or a hydrolyzable group on the silicon atom is 2 parts.
A silicon compound having one silicon atom and / or at least one hydroxyl group or hydrolyzable group on one silicon atom, and the total number of hydroxyl groups or hydrolyzable groups is 2 to 5 An adhesive composition comprising 0.1 to 50 parts by weight of a silicon compound having 2 to 20 silicon atoms and (c) 5 to 120 parts by weight of a tackifying resin. 2. The pressure-sensitive adhesive composition according to claim 1, wherein the rubber-based organic polymer as the component (a) is an alkylene oxide-based polymer. 3. The pressure-sensitive adhesive composition according to claim 2, wherein the rubber-based organic polymer as the component (a) is a polypropylene oxide-based polymer. 4. A rubber-based organic polymer as component (a) is a copolymer-based polymer obtained by polymerizing one or more vinyl monomers in the presence of an alkylene oxide polymer. The pressure-sensitive adhesive composition according to claim 1. 5. The pressure-sensitive adhesive composition according to claim 1, wherein the rubber-based organic polymer as the component (a) is a polymer-based polymer obtained by polymerizing one or more vinyl monomers. object. 6. The reactive silicon functional group in the component (a) has the general formula (1): (In the formula, R ¹ is a monovalent hydrocarbon group having 1 to 12 carbon atoms selected from an alkyl group and an aryl group, x is a hydroxyl group or a hydrolyzable group, a is 0, 1, 2 or 3, and b is The pressure-sensitive adhesive composition according to claim 1, which is a functional group represented by 0, 1 or 2, where 1 ≦ a + b ≦ 4 and n represents an integer of 0 to 19. 7. The pressure-sensitive adhesive composition according to claim 6, wherein the reactive silicon functional group in the component (a) is an alkoxysilyl group. 8. The pressure-sensitive adhesive composition according to claim 1, wherein the silicon compound as the component (b) is a silicon compound having a phenyl group bonded to a silicon atom to which a hydroxyl group or a hydrolyzable group is bonded. 9. A silicon compound as a component (B), The pressure-sensitive adhesive composition according to claim 8, which is a compound represented by the formula: wherein X represents a hydroxyl group or a hydrolyzable group. 10. A silicon compound of component (b) is A pressure-sensitive adhesive composition according to item 9.